In wireless communication, a user identity module generally needs to be deployed on a terminal. In the GSM standard, the user identity module is called a subscriber identity module SIM (Subscriber Identity Module); in the CDMA standard, the user identity module is called a user identity module UIM (User Identity Module); and in the UMTS standard, the user identity module is called a universal subscriber identity module USIM (Universal Subscriber Identity Module). Currently, the foregoing user identity module exists in a form of a physical card, and the terminal can be used only after the terminal is installed with the physical card.
With the development of technologies, virtual user identification data is further introduced, that is, a card in a physical form does not need to be inserted into a mobile phone, but data content corresponding to a user identity module (hereinafter referred to as virtual user identification data) is downloaded and stored in a secure storage area of the mobile phone, so as to achieve a same effect as a physical SIM card. In addition, the use of the virtual user identification data does not rely on a slot that is reserved for the physical SIM card during manufacturing of the mobile phone, and multiple pieces of virtual user identification data can be used in a mobile phone more conveniently. In the prior art, a mobile terminal is required to have a capability of accessing a communications network. However, under a specific condition, for example, when the mobile terminal is not within an operator service area, the mobile terminal cannot access the communications network, and therefore cannot access a remote database, so that the virtual user identification data cannot be downloaded.